Emulsion polymerization high-molecular dispersant for lithium battery substituted CMC and preparation method of emulsion polymerization high-molecular dispersant

Abstract

The invention discloses an emulsion polymerization polymeric dispersant for a lithium battery replacing CMC (Carboxy Methylated Cellulose), which mainly comprises unsaturated monomers, water, an emulsifier and a water-soluble initiator, and the emulsion polymerization is formed by polymerizing various unsaturated monomers and water in an emulsion prepared under the action of the emulsifier, the unsaturated monomer comprises but is not limited to one or more of acrylic acid, methacrylic acid, methyl methacrylate, styrene, vinyl acetate, butyl acrylate, 2-ethylhexyl acrylate, acrylamide and N-methacrylamide, and the main chain of the polymeric dispersant is a-C-C-bond. The invention adopts a simple and environment-friendly method to obtain a polymeric dispersant which can be designed on the main chain of a polymeric skeleton in advance, is more excellent than CMC, is more suitable for lithium batteries and can improve the performance of the existing lithium batteries to replace the CMC dispersant which is widely used nowadays.

Description

technical field [0001] The invention relates to the technical field of polymer materials, in particular to an emulsion polymerized polymer dispersant for lithium batteries instead of CMC. Background technique [0002] The traditional lithium battery negative electrode slurry uses CMC-carboxymethyl cellulose as a dispersant, and its production method is roughly as follows: immerse the degreased and bleached cotton thread in 35% of the proportion and immerse the degreasing and bleached cotton thread in 35% of the concentrated alkali , Soak for about 30min and take it out. The liquid caustic soda can be recycled, and the soaked cotton short-line is weighed on a flat press, and the lye is pressed out with a pressure of 14 MPa to obtain alkalized cotton. Put the alkalized cotton into the etherification kettle, add 15 parts of alcohol and stir Slowly add chloroacetic acid alcohol solution, complete at 30°C for 2 h, and then stir at 40°C for 3 h to obtain etherified cotton, add 12...

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Problems solved by technology

The liquid caustic soda can be recycled, and the soaked cotton short-line is weighed on a flat press, and the lye is pressed out with a pressure of 14 MPa to obtain alkalized cotton. Put the alkalized cotton into the etherification kettle, add 15 parts of alcohol and stir Slowly add chloroacetic acid alcohol solution, complete at 30°C for 2 h, and then stir at 40°C for 3 h to obtain etherified cotton, add 120 parts of alcohol (70%) to etherified cotton, stir for 0.5 h, add Adjust the pH value to 7 with hydrochloric acid, wash twice with alcohol, filter out the alcohol, air-dry at 80 °C, and pulverize to obtain the finished product. According to the different ingredients, it can produce low substitution degree (<0.4), medium substitution degree (0.4~ 1.2) The product, as can be seen from the above CMC structure and production process: CMC is made of natural substances as the base material, chemically modified, the main chain skeleton is fixed, and large performance optimization is not easy. The production process of CMC dispersant It is relatively complicated, using strong acid and strong alkali, the risk of chemical corrosion and burns is relatively high, and it produces more three wastes, which has a great impact on the environment and may leave more impurities in the product

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